Method of dyeing and/or washing fabric

ABSTRACT

A process is disclosed for continuously washing and/or dyeing a moist web of fabric as the web of fabric passes through a steam chamber in which a plurality of drums define a path of travel therethrough for the web of fabric. Steam is introduced into the chamber to provide a humid atmosphere therein and heat the fabric and at least some of the drums are heated to a temperature above the ambient temperature to apply heat directly to the fabric raising it above the temperature obtainable by use of a steam chamber alone. Additional heat is introduced into the chamber by heated panels mounted adjacent to the path of travel of the fabric between adjacent rollers which serves to maintain the temperature of the fabric as it passes from one heated drum to the next. The path of travel of the fabric passes through at least one trough which may contain water or other cleaning fluids therein to wash the fabric at elevated temperatures. The cleaning fluid is also sprayed onto the fabric as it moves along its path to aid in the washing operation.

United States Patent 1191 Rogers 1 Apr. 30, 1974 [76] Inventor: RobertKenneth Rogers, 4109 Laurel Dr., Raleigh, NC. 27612 22 Filed: Oct.13,1971

21 Appl.No.: 188,736

[52 US. Cl 8/175, 8/73, 8/l49.1, 8/149.3, 8/176, 8/D1G. 16, 68/5 1),68/5 E 511 1111. C1 D06p 5/02 [58] Field of Search 34/41, 119; 8/14,DIG. l6, 8/l49.l, 149.3; 68/5 D, 5 E

[56] References Cited UNITED STATES PATENTS 3,728,076 4/1973 vFleissner8/149.1 3,632,301 1/1972 Meier-Windhorst 8/176 3,401,412 9/1968Meier-Windhorst 68/5 E 3,396,415 5/1968 Meier-Windhorst 8/149.32,516,199 7/1950 Fry 34/119 3,619,103 11/1971 Williams et a1. 8/143,401,745 9/1968 Pato et a1 165/90 2,413,567 12/1946 Hornbosted 34/124OTHER PUBLICATIONS Kern, R., Modern Continuous Dyeing Processes 15 May1961, American Dyestuff Reporter pp. 45-52.

Primary ExaminerGeorge F. Lesmes Assistant Examiner-William R. Dixon,Jr.

[57] ABSTRACT A process is disclosed for continuously washing and/ordyeing a moist web of fabric as the web of fabric passes through a steamchamber in which a plurality of drums define a path of traveltherethrough for the web of fabric. Steam is introduced into the chamberto provide a humid atmosphere therein and heat the fabric and at leastsome of the drums are heated to a temperature above the ambienttemperature to apply heat directly to the fabric raising it above thetemperature obtainable by use of a steam chamber alone. Additional heatis introduced into the chamber by heated panels mounted adjacent to thepath of travel of the fabric between adjacent rollers which serves tomaintain the temperature of the fabric as it passes from one heated drumto the next. The path of travel of the fabric passes through at leastone trough which may contain water or other cleaning fluids therein towash the fabric at elevated temperatures. The cleaning fluid is alsosprayed onto the fabric as it moves along its path to aid in the washingoperation.

7 Claims, 1 Drawing Figure MTENTEDAPRSOlBY 3.807.950

INVENTOR. ROBERT KENNETH BY ROGERS LERNER, DAVID & LITTENBERG METHOD orDYEING AND/R WASHING FABRIC FIELD OF THE INVENTION This inventionrelates to a process for dyeing and/or washing a web of fabric.

BACKGROUND OF THE INVENTION Fabric has been dyed and the dyed fabricwashed for thousands of years. New fabrics have of course beencontinuously introduced during the years, including synthetic fabrics.As each new fabric is developed, the dyeing and washing characteristicsthereof must be taken into account to determine which of the prior artprocesses are most suitable thereto or if, in fact, new procedures mustbe developed. Notwithstanding the longhistory of the fabric dyeing andwashing industry, optimum techniques have not yet been developed.

Perhaps the most common method employed for dyeing fabrics are the batchprocesses in which a quantity of fabric isimmersed in an aqueoussolution of a dye. The dye normally is heated to a temperature in therange of about 260 F. The fabric is left therein for a period of timetypically an hour or more. There are two interrelated reasons why such along time interval at such a relatively low temperature is required.First the dye because it is in an aqueous solution is not sufficientlyconcentrated to dye the fabric at a high rate of speed. Secondly thefabric can withstand high temperatures for only short intervals of time.Therefore, since a long interval of time is required due to the lowconcentration of dye, the temperatures obtainable must be lowered toprotect the fabric again extending the time interval to complete thedyeing process.

The use of the lower temperature complicates the dyeing process furtherby introducing Barree patterns in the material. The Barree patterns aredetermined by and due to the previous history of the fibers in thefabric during manufacture thereof and tension developed in the fibersduring knitting of the fabric. It has been found that dyeing at highertemperatures can minimize the sensitivity of the material to temperaturevariation with respect to the Barree problem but the period of dyeing inan aqueous solution will not allow this.

A further drawback of the above process is that the fabric being dyedoccupies the processing equipment for an extended period of time. Thus,if a sufficiently fast continuous dyeing process were developed, theactive floor space of the dyeing facility could be more economicallyutilized.

To overcome these problems, a continuous dry dyeing process wasdeveloped. This process involves the application of a paste-likeconcentrated dye to the fabric and then passing of the fabric through aheated area (at approximately 425 F.) for a short interval of time. Theheat is normally supplied by open gas flames. This process tends tominimize the Barree problem but results in a low quality relativelystiff fabric due with poor hand" due to the dry heat. The fact that gasflames are necessary to produce the desired heat precludes thepossibility of maintaining a sufficiently humid environment.

Various attempts have been made to overcome this problem by passing afabric having a concentrated dye coating thereon through a steam chamberto provide a rapid continuous moist dyeing process which produces a highquality fabric. In such a continuous process, the fabric must pass intoand out of a dyeing chamber which can, therefore, not be sealed. It hasbeen found that the temperature of a dyeing chamber cannot be raisedabove approximately 220 F. by the introduction of steam therein withoutpressurization. As a result, it appears that the prior attempts atcontinuous moist dyeing in steam chambers have been abandoned.

BRIEF DESCRIPTIONOF THE INVENTION The present invention overcomes theabove and other problems by providing a process for continuously moistdyeing a web of fabric which includes the steps of applying aconcentrated dye to the surface of the fabric and then heating thefabric to a temperature of above 220 F. in a humid atmosphere. Theprocess takes place in a processing chamber formed in a machine throughwhich the web of fabric is passed. A plurality of drums are mounted inthe chamber to define a path of travel for the web of fabric. Steam isintroduced into the chamber to heat the chamber to an ambienttemperature of about 220 F. to supply the additional heat to the fabric.Still further, heated panel members or panels are disposed adjacent thepath of the fabric at at least some of those portions between heateddrums to maintain the temperature of the fabric above 220 F. andpreferably above 300 F.

A cleaning trough, also included in the machine, is used for holding areservoir of fluid through which the fabric passes on its path oftravel. Cleaning fluid may also be sprayed onto the fabric adjacent tothe trough. A second trough is included in the machine and spans theexit opening from the chamber to provide a fluid seal for preventingsteam from leaking out of the chamber and also for aiding in washing ofthe fabric.

It has been found that the washing of the fabric after dyeing at theelevated. temperatures is sufficiently advantageous over previouswashing methods that according to this invention fabric is washed by thesteps of heating the fabric to a temperature of approximately 220 F. ina humid atmosphere and while maintaining the fabric under tensionimmersing it in a clean fluid.

DESCRIPTION OF THE DRAWINGS The sole FIGURE is a sectional side view ofa machine for processing a web of fabric in accordance with theteachings of this invention.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the sole FIGUREof this invention wesee a machine 10 having a chamber 11 formed therein.A web of fabric 12 passes through a path in the machine defined byrollers 13 through 22. The web of fabric 12 enters the chamber through aconventional entry port 23 and exits therefrom through an exit opening24. i

The drums 13 through 19 are heated drums which may have steam or heatedoil therein. The drum 13 may be heated to, for example, a temperature ofbetween 220 to 250 F. The drum 14 may be heated to, for example, atemperature between 250 and 300 F. The drum 15 may be heated to, forexample, a temperature between 300 and 350 F. while the drums 16 and 17may be heated to the'same temperature of between 350 and 500 F. Thedrums l8 and 19 may be maintained at a temperature of about 200 F.

The drum 20 is perforated and has spray nozzles 26 and 27 therein tospray a cleaning fluid such as water on the web of fabric 12 as itpasses therearound. Spray pipes 28, 29 and 31 may spray cleaning fluidon the outside of the fabric as it passes around the drums 19, and 21respectively. The drums 20 and 21 are perforated. A plurality ofperforated steam pipes 32 through 34 introduce steam into the chamber 11in the area of the drums 13 through 17.

A plurality of panels 35 through 39 heated to a temperature of, forexample, about 500 F extend from the walls of the chamber 11 between theweb of fabric 12 as it passes between the drums 15, l6, 17, 18 and 19 toaid in maintaining the temperature of the fabric above the ambienttemperature available with steam alone as it passes between the drums.

The steam introduced through the perforated steam pipes 32 through 34may be superheated to a temperature of in excess of 400 F. However, theequilibrium temperature in the chamber due to the introduction of thesuperheated steam is typically in the range of 220 F. The heat suppliedto the fabric directly from the drums enable the fabric 12 to be heatedabove the temperatures normally obtainable in non-pressurized steamchambers. As noted previously, the heat supplied by the panels 35through 39 help maintain the fabric 12 at the elevated temperatures asit passes between the respective drums.

A trough 41 is located in the chamber 11 partially surrounding the drum18. A second trough 42 partially surrounds the drum 22 and spans theexit opening 24.

in operation the web of fabric 12 is passed between a pair ofconcentrated dye applying pads 43 and 44 so that the web of fabric 12 iscoated on both sides with the concentrated dye as it enters the chamber11 through the conventional entry port 23. If for example the fabric 12is textured polyester, the concentrated dye applied to the web of fabric12 can comprise a dispersed dye in a dispersing agent, a carrier to helpswell the fiber, and gum and acetic acid to control the pH duringdyeing.

As the coated web of fabric 12 enters the entry port 23 it passesbetween heated pipes 46 and 47 and under heated pipe 50 which helpprevent condensation and dripping of the steam onto the fabric. Thechamber 23 is also subject to suction via a suction pipe to helpevacuate the chamber 23 thereby preventing excess steam build up anddripping.

As the web of fabric 12 passes over the rollers 13, 14 and 15 thetemperature thereof builds up through a combination of the exposure tothe steam environment and the heat directly applied from the drums. Itwill be noted in this embodiment that the temperature of the drumsprogress from the temperature of the steam environment to the ultimatedye fixing temperature arrived at at the drum 16. This is done sincealternate sides of the fabric pass over alternate drums which couldresult in facing of the material if dye fixation occurred rapidly on oneside.

After the fabric 12 passes over the last dye fixing drum 17 it isimmersed in a washing fluid in the trough 41. A chemical feed member 48is provided to introduce cleansing or pH fixing fluids into the trough.It will be noted that drum 18 is at a lower temperature than the dyefixing drums but yet is still at an elevated temperature so that thestill hot fabric 12 can be more easily washed. The fabric 12 moves fromthe drum 18 to the drum 19 where it is sprayed from the pipe 28 on theright hand side. It should be noted that a baffle 49 is interspersedbetween the fabric coming to and leaving the drum 19. This is done sothat dirty water dripping off the fabric after it leaves the trough 41will fall back towards the trough 41 rather than onto the fabric furtherdown the line.

After leaving the drum 19 the fabric 12 moves onto the drum 20 where itis sprayed on both sides by the perforated pipe 29 and the spary heads26 and 27. The fabric 12 then is passed over perforated drum 21 forfurther spraying from the pipe 31. It should again be noted that abaffle 51 is provided to insure that whatever water drips therefrom isfed back rather than forward onto the cleaner fabric. The fabric 12 thenpasses around the drum 21 through trough 22 which is filled above theexit opening 24 so that the cloth in its final washing operation insidethe chamber 11 passes out of the chamber 11 through a liquid barrierwhich helps maintain the steam in the chamber 11.

After leaving the chamber 11 the web of fabric 12 is passed over avacuum slot 52 to draw off moisture. The fabric 12 is then passedthrough normal processing and dye fixing baths before being wound on abolt or folded.

It has been found that the dyeing of fabric in this manner allows highquality dyeing to be achieved in as little as a 2-minute interval. ithas also been found that the washing of the fabric in the steam chamberat the elevated temperatures produces more efficient washing than washeretofore available. To this end the machine 10 may be employed evenwithout the heated drums to wash webs of fabric. The fact that the webof fabric is held in open width on the roller during the raising andlowering of the temperature under humid and moist conditions preventswrinkling thereof due to thermal shock.

It should of course, be understood that the drums 13 through 22 aredriven to move the fabric through the chamber 12. Conventionaldifferential drums could be used to account for stretching of the web offabric 12 as it passes through the machine.

Access doors 53 and 54 are provided one on each side of'chamber 11 (onlyone of each such door being shown). Access door 53 comprises a window 56and access door 54 comprises window 57 for inspection purposes. It willbe appreciated that these doors can be opened or removed enabling one towork within chamber 11.

The baffles may be pivotally and/or removably mounted as desired to aidin the maintenance of the machine and in the treating of a web of fabrictherein. In this regard, the drums may also be removably mounted.

it should be understood that other classes of dyes may be used incombination or separate from the disperse dyes cationic, acid, etc.

It should be understood that while this invention has been describedwith respect to the specific embodiment thereof, numerous others willbecome obvious to those of ordinary skill in the art in light thereof.

What is claimed is:

1. A process for continuously moist dyeing a web of fabric including thesteps of:

applying a concentrated dye to the surface of said fabric;

heating said fabric to a temperature within the range of from about 200to about 250 F;

then heating said fabric to a temperature varying in a dispersed dye ina dispersing agent;

the range of from about 300 to about 500 F; and a carrier to help swellthe fiber of the fabric;

a gum; and cooling said fabric to a temperature of about 200 F aceticacid.

or below. 5 5. The process in accordance with claim 1 wherein 2. Theprocess as defined in claim 1 in which heat is said fabric is heated inan environment saturated with supplied by direct contact to said fabric.steam.

3. The process as defined in claim 1 in which said 6. The process asdefined in claim 1 including the web of fabric is moving along a pathand heat is supstep of applying cleaning fluid to said fabric during orplied to said fabric by direct contact to said fabric at 10 after saidcooling step. preselect spaced positions on said path. 7. The process asdefined in claim 6 wherein said 4. The process as defined in claim 3 inwhich said cleaning fluid is water. concentrated dye includes:

2. The process as defined in claim 1 in which heat is supplied by directcontact to said fabric.
 3. The process as defined in claim 1 in whichsaid web of fabric is moving along a path and heat is supplied to saidfabric by direct contact to said fabric at preselect spaced positions onsaid path.
 4. The process as defined in claim 3 in which saidconcentrated dye includes: a dispersed dye in a dispersing agent; acarrier to help swell the fiber of the fabric; a gum; and acetic acid.5. The process in accordance with claim 1 wherein said fabric is heatedin an environment saturated with steam.
 6. The process as defined inclaim 1 including the step of applying cleaning fluid to said fabricduring or after said cooling step.
 7. The process as defined in claim 6wherein said cleaning fluid is water.